Ohmic contact can be formed in one process step.
John H. Glenn Research Center, Cleveland, Ohio
Electrical ohmic contacts can be simultaneously formed on silicon carbide (SiC) semiconductors having donor and acceptor impurities (n- and p-type doping, respectively). This implies that such contacts can be formed on SiC layers in one process step during the fabrication of the semiconductor device. This also means that the multiple process steps for fabricating contacts onto n- and p-type surfaces, which is characteristic of the prior art, will be greatly reduced, thereby reducing time and cost, and increasing yield (more process steps and complexity increases chances for lower yields). Another significance of this invention is that this scheme can serve as a non-discriminatory, universal ohmic contact to both n- and p-type SiC, without compromising the reliability of the specific contact resistivity when operated at temperatures in excess of 600 °C.

This innovation has applications in aircraft leading edge slats and rotor tips for propulsion components on both aircraft and rotorcraft, as well as on wind turbines.
Langley Research Center, Hampton, Virginia
Aircraft noise is a significant problem with both economic and public health implications, especially for communities near airports. As a result, increasingly stringent constraints are being placed on aircraft carriers worldwide to reduce this noise. The current disclosure focuses on airframe noise generated at or near the surface of the flap-side edge.

Marshall Space Flight Center, Alabama
Radiation-cooled, bipropellant thrust chambers are being used for in-space propulsion. To increase the performance of radiation-cooled engines, improved chamber materials are needed that will allow higher operating conditions (pressure and temperature), better resistance to oxidation, and reduced mass. During this effort, an innovative composite thrust chamber is being developed that will incorporate advanced hafnium oxide and iridium liner techniques as well as replacing the expensive, high-density rhenium with a low-mass carbon-carbon (C–C) structural wall.

John H. Glenn Research Center, Cleveland, Ohio
Composite turbine blades are currently fabricated by laying up multiple layers of fibers in the form of either unidirectional prepregs or thin woven cloth. Composites formed in this manner have poor through-thickness strength. It is also difficult, if not impossible, to form trailing edges as thin as necessary for optimum engine performance.

A full-cell configuration with a limited electrolyte in the cell is used to reflect the actual cell build conditions.
John H. Glenn Research Center, Cleveland, Ohio
A quick and cost-effective evaluation/screening technique for new battery chemistries was developed that integrates the individual advanced cell component in a full-cell format to identify the critical issues, such as cell component interaction and compatibility before proceeding to commercial production. To make the assessment more practical, a unique way of introducing limited electrolyte was developed. This technique enabled fast and low-cost screening to address any potential issues.

Nanometer-scale materials can provide smaller devices than those currently available.
Ames Research Center, Moffett Field, California
Recently, one-dimensional (1-D) nanostructures, such as nanowires and nanotubes, have become the focal point of research in nanotechnology due to their fascinating properties. These properties are intrinsically associated with low dimensionality and small diameters, which may lead to unique applications in various nanoscale devices. It is generally accepted that 1-D nanostructures provide an excellent test ground for understanding the dependence of physical, electrical, thermal, optical, and mechanical properties on material dimensionality and physical size. In particular, 1-D semiconductor nanostructures, which exhibit different properties as compared with their bulk or thin film counterparts, have shown great potential in future nanoelectronics applications in data storage, computing, and sensing devices.

Question of the Week

This week's Question: A recent study created by the Arizona-based Paragon Space Development Corporation says its life support system could help humans survive on Mars. The proposed Environmental Control and Life Support System, the company says,...